Rb25det Coil replacement Debate!!

[rb25drag]

Alright I need some advice, I have narrowed my problem down to the coils being weak. I think The Gizzmo launch control I installed has killed them, I don't make any power over 5,000 RPM's and its running pig rich, I also have full 15lbs of boost on WOT, it just won't pull, I have not changed my tune either, The more I ran it at the track the worse it got.

My question is, I know these stock coils are old. I would like a direct replacement. I have looked at the split fires, But i have read they have had issues with misfires also.

Since Im going to be using the launch control at the track ALOT, I need a coil that im not going to kill. Is a Stock OEM going to handle the abuse or am I better off going with the SplitFires?

Also does anyone have the OEM coil replacement part #? anyone have any Idea of the price of a dealer replacement?

[gawdzilla]

the dealer ones (infiniti q45, forget which cylinders. something like 1 and 5 but don't quote me on that) are a little over $100 a piece. added up, that's $600 for new oem.

splitfires are 450-500, and IMO are no WORSE than oem. it is arguable whether or not they are much better. but worst case, you are getting a new set of coils vs. whatever old crap came with your motor. i am running them now and they are okay.

i assume you tried putting in new plugs and regapping? plugs foul easy and even easier with a misfiring system. sounds like you might also have a boost leak. is your car missing really bad or is it just not pulling hard? if it runs smooth and just doesn't pull you probably have a boost leak or your tune is out.

[craz4240]

Why not do a GNX coil retrofit??

Is your motor series 1 or 2???

[gawdzilla]

Why not do a GNX coil retrofit??

because not everyone wants to go backwards in technology from coil on plug to wasted spark, plug wires, and a big box you need to find somewhere to hide in your engine bay.

[240z4u]

I have to say, I find it interesting that everyone loves the buick V6 coil conversion. Don't church it up, its not a "GNX" or even "GN" coil set. Its the same coilset that comes on the n/a crapwagons too. Its a fine basic solution yes. The buick guys have spark problems with those coilpacks too. I had one (a GN).

You can get a coil similar to the buick coil from summit that will allow you to do a non-wasted spark setup. I forget the real name, sorry.

Also gawdzilla, I really don't agree with your suggestion that you are going backwards in technology by going to a setup that is not coil on plug. Granted 80s buick technology is old.

Evan

[gawdzilla]

i'm not saying the wasted spark technology won't work. carbs work too and also work great. my view of technology tends to follow what current production cars are doing. most are direct ignition now... so i would say wasted spark is going backwards.

[rb25drag]

Well, here is how it started. It first started when I went from 1st to 2nd gear it totally dropped 1-2 cyl for about 5 seconds then picked back up and ran fine. It only done it when I shifted and it dropped RPM's.

Then the more I ran the car it got to were it started misfiring anything above 5,000RPM's. On my last pass of the night it would not even rev over 5,000 While on WOT, and the A/F readings on my wideband went to 9.0 Which is Pig rich and it was holding 15lbs of boost, Not dropping off. I know there is no boost leaks and I also no its not a spark plug foul, It Revs Fine and idles good, no missing like a fouled plug would cause.

I pulled the plugs, They were Gray looking which seemed to be not too rich and not too lean, The Gaps are .022 just as I set them.

I have a s2 motor, Which if I went to the Buick coils I would have to buy a igniter and hack my harness, Which I don't really wanna do. I would rather just buy what fits and plugs in and go.

Im also afraid of the buick coil not working with my launch control which I just spent 300$ on.

Im almost 100% my coils are getting weak. I don't think they have been in the greatest shape from day 1, I just didn't wanna spend more $ than I had too.

I mean, Something is Def screwed, I went from a 7.80@91 in the 1/8th to 10.02 @ 67, on the same tune.

[crccustoms]

i really suggest you run an ignition box like msd's dis with good coils and wires because the potential output of that setup beats anything ive seen from a coil on plug setup, and if your serious into drag racing you've probably seen them, now ive heard of people using the summit part (Summit SUM-850592-1) which is a coil on plug setup for ford vehicles but im afraid i cannot offer much information on that swap, and if your afraid to revert to the plug wire setup and think the coil over plug setup is better, theres alot of racing crews from drag racing to circle tracks that still trust the plug wire setup, theres not really that much resistance compared to the plug over coil setup, and you'll have a much more reliable ignition system

[rudedrift]

i have an rb25 sII and ever since i turned up the boost to 10psi with an rb20 wastegate i've had the same problems. changed coil packs and plugs and all that.i think i'm goin to run the gm set-up.

[Blown240sx]

IF you want a strong setup we ran 6 MSD SS blaster coils on my friends 400 whp RB and the spark output puts any of the factory or aftermarket replacments to shame and cost about the same..

How to....

take your coils out and pull out the coil harness where its easy to see.

Mark each of the center wires they should be some combination of red/xxxx another color. Number them so you will remember what cylinder they fire.

Start at the ignitor and de loom the harness towards the coils. You will have 3 wires to each coil. 1 power, 1 constant ground, and 1 switch ground from the Ignitor.

The factory ground going to each coil will not be used.

Take the factory power and either daisy chain it across all the MSD coils or use it as a switch 12v for a thicker Relayed system. RecommendedWe used 10 gauge wire and a high amp replay since the factory wire is thinner gauge. You can use the factory power wire to switch your relay.

Now run your power, daisy chaining it off every coil to (+) side on the coil.

Now for the switch. Youll need to extend all the wires coming from the ignitor. The ignitor is a large relay essentially and it sends ground pulse.

Run a lead to each coil in the order you marked before removing the harness.This goes to the (-) negative side of the coil.Then use the boot kit they come with and make your wires and mount the coils somewhere and fire it up.

[Largekid]

IF you want a strong setup we ran 6 MSD SS blaster coils on my friends 400 whp RB and the spark output puts any of the factory or aftermarket replacments to shame and cost about the same..

How to....

take your coils out and pull out the coil harness where its easy to see.

Mark each of the center wires they should be some combination of red/xxxx another color. Number them so you will remember what cylinder they fire.

Start at the ignitor and de loom the harness towards the coils. You will have 3 wires to each coil. 1 power, 1 constant ground, and 1 switch ground from the Ignitor.

The factory ground going to each coil will not be used.

Take the factory power and either daisy chain it across all the MSD coils or use it as a switch 12v for a thicker Relayed system. RecommendedWe used 10 gauge wire and a high amp replay since the factory wire is thinner gauge. You can use the factory power wire to switch your relay.

Now run your power, daisy chaining it off every coil to (+) side on the coil.

Now for the switch. Youll need to extend all the wires coming from the ignitor. The ignitor is a large relay essentially and it sends ground pulse.

Run a lead to each coil in the order you marked before removing the harness.This goes to the (-) negative side of the coil.Then use the boot kit they come with and make your wires and mount the coils somewhere and fire it up.

Yes, I own that car now, and have no problems w/ it whatsoever...if you need me to help out anyway with getting this setup to work for you, let me know...i'll help where I can

edit...didn't see the pictures, but thats my engine bay in the pics he posted lol

[Blown240sx]

Me and my friend you bought it from did that install.

[rudedrift]

sweetness.that's whats up.i'm though with factory coilcraps

[rb25drag]

I really like that MSD setup, Thats Clean!!

My only question is on a SII we don't have ignitors. Is this a problem running that setup?

[Carl H]

or how bout install a quest alternator because the stock 80a pos cant keep up with the amp draw from your efans and thus killing spark.

[rb25drag]

I installed the quest and it worked for about 1 day and died!! Lost 80$ on the deal, The stock alternator is doing fine. So No need to change something thats not broke, I didn't notice any difference with the quest either.

[Coolwhip]

I have a set of S2 coils for sale. As well, I'm having a shipment of upgraded coil units that I'll start distributing pretty soon. Once I have a personal review on a set, I'll let you know. But for a set that perform just as well as any spitfire or any direct ignition unit and such will only set you back $499 for a set.

[rb25drag]

Sweet, How long will it be before you get the upgraded coils?

[craz4240]

because not everyone wants to go backwards in technology from coil on plug to wasted spark, plug wires, and a big box you need to find somewhere to hide in your engine bay.

Yeah it kindof is but it works equally as good as stock and is ALOT cheaper to replace when the time comes.

[Blown240sx]

The S2 should work the same. Since they still send a signal directly to each coil. It should work the same. All ignition systems like this are switch ground.

[crccustoms]

good clean setup blown240, and i agree you'll end up spending as much or more with the stock style coils than the msd setup with 8mm that can be achieved for around $350 from summit, and if you need more spark due to higher compression $400 buys you higher output coils and 10 mm wires, the summit (sum-850500m) coils are rated at 51,000v and have enough power to fire the discovery space shuttle to the next galaxy, there $50 a piece at summit, $75-100 for a good set of wires and your set, and you would go about hooking up that setup the same way as the msd, negative being the trigger, which comes from the harness that your stock setup uses

[240z4u]

Coil on plug is fine when its not a total cooker under the hood. I really think thats what helps lead to the demise of the stock coils. I have wondered forever if having a phonelic coilpack bracket made would help keep them cooler. You would have to run ground straps from the coil body to the valvecover though.

Anyway, the MSD setup looks pretty good too.

Evan

[Cjmartz2k]

Have you tried cleaning the contact inside it i.e. popping off the boot, removing the spring, and sticking a dremel down in there to remove the crap that builds up? Just hit it until it looks like shiny brass down inside the coil pack and give it a shot. Mine sucked under 22psi until I did that, and now they are handling 26psi with no problems.

[Blown240sx]

good clean setup blown240, and i agree you'll end up spending as much or more with the stock style coils than the msd setup with 8mm that can be achieved for around $350 from summit, and if you need more spark due to higher compression $400 buys you higher output coils and 10 mm wires, the summit (sum-850500m) coils are rated at 51,000v and have enough power to fire the discovery space shuttle to the next galaxy, there $50 a piece at summit, $75-100 for a good set of wires and your set, and you would go about hooking up that setup the same way as the msd, negative being the trigger, which comes from the harness that your stock setup uses

I cant take much credit since the previous owner (brandon) did the wiring but I fully understand how it was done and how it works.

[gawdzilla]

Well, here is how it started. It first started when I went from 1st to 2nd gear it totally dropped 1-2 cyl for about 5 seconds then picked back up and ran fine. It only done it when I shifted and it dropped RPM's.

Then the more I ran the car it got to were it started misfiring anything above 5,000RPM's. On my last pass of the night it would not even rev over 5,000 While on WOT, and the A/F readings on my wideband went to 9.0 Which is Pig rich and it was holding 15lbs of boost, Not dropping off. I know there is no boost leaks and I also no its not a spark plug foul, It Revs Fine and idles good, no missing like a fouled plug would cause.

I pulled the plugs, They were Gray looking which seemed to be not too rich and not too lean, The Gaps are .022 just as I set them.

I have a s2 motor, Which if I went to the Buick coils I would have to buy a igniter and hack my harness, Which I don't really wanna do. I would rather just buy what fits and plugs in and go.

Im also afraid of the buick coil not working with my launch control which I just spent 300$ on.

Im almost 100% my coils are getting weak. I don't think they have been in the greatest shape from day 1, I just didn't wanna spend more $ than I had too.

I mean, Something is Def screwed, I went from a 7.80@91 in the 1/8th to 10.02 @ 67, on the same tune.

your wideband is going to show false richness if you are misfiring. there is unburnt fuel that is coming out of your exhaust each time you miss a spark. that is probably why your wideband is showing rich.

did you try putting in new plugs? i always keep a spare set in my toolbox now. in my experience, once plugs have seen a bit of missing (or poor tune), they don't perform nearly as well as a new set. i have tried torching the plugs to clean them up too. if you're running colder plugs, they will foul easier too. just grab a fresh set to rule out the plugs themselves. they're what? $1.50 a piece?

[Carl H]

i still say its a power issue...stock coils will light off some pretty intense charge pressures...if you have a pfc check out the battery voltage on full boost with the fans on, anything less than 13.8v will cause misfires.

[Blown240sx]

Yea but the power fc has maps in it that will lower everything if that occurs. It has maps for low voltage compared to the ignition.

[Carl H]

true but in reality they dont work well, trust me i had a 25pfc on my 20 for a hot second there and it would quite literaly poop out a brick when voltages would drop below 13.5 or so...ended up fitting a quest alternator and that problem dissapeared.

[rb25drag]

I haven't tried to clean the coils yet. Ill def look into that. I do have a new set of plugs but have not tried them yet. I got busy and didn't have time to throw them in. I will spend more time on it this weekend.

I really don't think its electrical, Its def something with the spark.

I am running a # 4 cold plug. Always had great results on this motor with it. Been running those kind for 2 years. I have about 26 track passes on these plugs.

[Carl H]

rotfl.classic.

I really don't think its electrical, Its def something with the spark.

Ive tried to help push you in the right direction man but if you dont want to listen then thats cool too, i think that you fail to see that an 80a alternator cannot provide power to a car that has to run high amperage drawing electric fans, provide power to 6 coils which are individualy fired as well as 6 injectors all while powering the car's electronics and interior.Stick a multimeter on the battery terminals and run leads into the cabin and see what voltage looks like with everything on and running, i bet it will be low 13's at best...most likely high 12's.